New rules which set limits on how much pollution farmers can put in to waterways are set to have a huge impact on how we use land and water. Environment Minister David Parker said at the weekend that the new system could lead to limits on cow numbers. But the story is developing this morning. Guyon Espiner spoke to the Minister a short time ago and he conceded that it could also dramatically change land values. And adding to the complexity Mr Parker says that the vexed issue of Māori rights and interests in water needed to be resolved at the same time. Hear full interview